Regional fracture patterns around volcanoes: Possible evidence for volcanic spreading on Venus
نویسنده
چکیده
Magellan data show that the surface of Venus is dominated by volcanic landforms including large flow fields and a wide range of volcanic edifices that occur in different magmatic and tectonic environments. This study presents the results from a comprehensive survey of volcano– rift interaction in the BAT region and its surroundings. We carried out structural mapping of examples where interaction between volcanoes and regional fractures results in a deflection of the fractures around the volcanic features and discuss the nature of the local volcano-related stress fields that might be responsible for the observed variations of the regional fracture systems. We propose that the deflection of the regional fractures around these venusian volcanoes might be related to volcanic spreading, a process recognized as of great importance in the tectonic evolution of volcanoes on Earth and Mars, but not previously described on Venus. © 2008 Elsevier Inc. All rights reserved.
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